Method and system for evaluating and optimizing propulsion performance of medium and high speed ship

Abstract

The invention provides a method and a system for evaluating and optimizing the propulsion performance of a medium-high speed ship, and the method comprises the steps: gradually carrying out the initialization and iterative solution of a flow field, gradually carrying out the step-by-step progression of a plurality of steps, providing a proper initialization flow field for a multi-stage movement problem, gradually releasing the movement of each stage, enabling a paddle coupling flow field to be gradually stable and tend to a final real flow field, and achieving the evaluation and optimization of the propulsion performance of the ship. The smooth transition of the flow field, the ship body stress and the motion is ensured, and the robustness and the convergence efficiency of a numerical calculation model are improved; a propeller multi-rotating-speed adjusting method in self-propulsion calculation is established, and a convergence judgment standard, calculation result extraction and ship self-propulsion performance forecasting method is calculated; by constructing an optimized method-driven medium and high-speed ship type transformation, self-propulsion performance evaluation process and optimization design process method, the problem that full-process automation cannot be realized due to manual interaction in the process is solved, and the application effect of the optimization theory in medium and high-speed ship type optimization design is improved.

Description

Technical Field

[0001] The present invention relates to the technical field of computer simulation design, and in particular to a method and system for evaluating and optimizing the propulsion performance of a medium- and high-speed ship. Background Art

[0002] The rapid performance index of ships is one of the core technical indicators that are focused on in ship design and development. At present, with the development of ship CFD technology and parametric modeling technology, a method of ship optimization design process driven by optimization method based on optimization theory has emerged in the field of ship optimization design research. This method can realize the automation of ship transformation, CFD solution and result analysis process, which can reduce manual operations and effectively get rid of the high dependence of ship design on engineers, and realize the deep optimization design of ship performance facing the global design space. It has achieved good application results in the optimization design of resistance performance of various types of ships.

[0003] However, it is difficult to achieve good engineering applications for the optimization design of the propulsion performance of medium- and high-speed ships. The main reason is that the use of viscous flow method to calculate the self-propulsion performance of medium- and high-speed ships requires consideration of the coupled numerical simulation of multi-stage motions such as the floating state changes during ship navigation and the rotation of propellers. Solving the physical problems is complex and the amount of calculation is large. In order to improve the calculation efficiency to a certain extent, a large amount of human intervention is required in the solution process. At the same time, the self-propulsion calculation results need to be interpolated through multiple propeller speeds to obtain the self-propulsion point. The result analysis process requires the combined analysis of multiple examples. The full process integration and automation have not yet been achieved, which makes it impossible to achieve automatic optimization design of ship propulsion performance based on optimization algorithms. Summary of the invention

[0004] In order to solve the problems of a large amount of manual adjustment in the existing methods during the numerical evaluation of the propulsion performance of medium and high-speed ships, the inability to achieve integrated automation of the entire process, and the inability to achieve optimization algorithm-driven optimization design of the self-propulsion performance of ships, the present invention provides a method and system for evaluating and optimizing the propulsion performance of medium and high-speed ships, which solves the integrated packaging and automation of the calculation and evaluation process of the self-propulsion performance of ships, and improves the application effect of optimization theory in the optimization design of medium and high-speed ships.

[0005] The technical solution of the present invention is as follows:

[0006] A method for evaluating and optimizing the propulsion performance of a medium- and high-speed ship type comprises the following steps:

[0007] Step 1: Establishing the numerical calculation domain of the self-propulsion performance of medium- and high-speed ships: Obtain the sample ship three-dimensional geometric model file, extract the automated ship characteristic parameters; construct a coordinate system group based on the automated ship characteristic parameters and navigation parameters; the coordinate system group includes a global coordinate system, a hull motion coordinate system, and a propeller rotation coordinate system; based on the coordinate system group and the automated ship characteristic parameters, establish the numerical calculation domain of the self-propulsion performance of medium- and high-speed ships:

[0008] Step 2: Establish an integrated method for the numerical calculation process of medium- and high-speed ship self-propulsion performance;

[0009] Step 2.1: Establish a CFD numerical calculation model for the self-propulsion performance of medium- and high-speed ships by conditionally configuring the numerical calculation domain of the self-propulsion performance of medium- and high-speed ships in step 1: The conditional configuration includes: selecting the Reynolds average viscous flow calculation method as the basic method for solving the model, selecting the SST Kw turbulence model and the standard wall function to handle the ship-propeller coupled flow field simulation, selecting the VOF method to calculate the free liquid surface of the ship, using the method of alternating the motion reference coordinate system and the sliding grid to simulate the rotation of the propeller, and selecting the overlapping grid method to calculate the hull pitch and heave freedom movement;

[0010] Step 2.2: Establish an automatic control method for the CFD numerical calculation model of the self-propulsion performance of the medium- and high-speed ship described in step 2.1: 1) Set the numerical solution convergence control process and divide the calculation process: the calculation process includes the flow field initialization stage, the hull flow field preliminary calculation stage, the propeller coupling flow field numerical calculation stage, the hull motion superimposed propeller rotation flow field calculation stage, the refined numerical simulation stage, and the ship self-propulsion point calculation and ship self-propulsion performance analysis stage; 2) Formulate the solution control method and convergence judgment method for the hull flow field preliminary calculation stage, the propeller coupling flow field numerical calculation stage, the hull motion superimposed propeller rotation flow field calculation stage and the refined numerical simulation stage in sequence;

[0011] Step 2.3: Calculate the propeller received power: Combine the medium-high speed ship self-propulsion performance CFD numerical calculation model described in step 2.1 and the automatic control method of the model calculation process established in step 2.2 to establish a medium-high speed ship self-propulsion performance numerical calculation model, input the sample ship type three-dimensional geometric model file obtained in step 1, complete the medium-high speed ship self-propulsion point acquisition and ship self-propulsion performance characteristic parameter calculation and analysis, and output the propeller received power as the ship self-propulsion performance characteristic quantity;

[0012] Step 3: Establish a method for optimizing the self-propulsion performance of medium- and high-speed ships:

[0013] Step 3.1: Construct a 3D geometric model file of the deformed ship based on the hull deformation constraint conditions, and input it as a sample 3D geometric model file into step 2 to calculate the received power P of the ship propeller. D, to realize the numerical calculation of the self-propulsion performance of the modified ship type;

[0014] Step 3.2: Use genetic algorithm to optimize step 3.1 to obtain the power P received by the ship propeller D , taking the tail deformation parameter as the independent variable, the calculated ship propeller received power as the objective function, and the ship type optimization design target P D The value required is used as the optimization target of the ship's self-propulsion performance, that is, the preset termination condition of the genetic algorithm; the ship propeller receives the power P after automatic output optimization D .

[0015] Preferably, the method for extracting the automated ship type characteristic parameters in step 1 is:

[0016] Step 1.1: Obtain the sample ship type 3D geometric model file (IGS / IGES format). The length unit of the 3D model file is "meter". The origin of the model coordinate is located at the intersection of the ship's stern perpendicular and the ship's baseline. The X-axis direction of the coordinate system is from the stern to the bow, the Y-axis direction is from the starboard side to the port side, and the Z-axis direction is from the bottom of the ship to the vertical upward direction of the deck;

[0017] Step 1.2: Extracting three-dimensional geometric characteristic parameters of the ship type: Based on the sample three-dimensional geometric model file of the ship type described in step 1.1, extracting three-dimensional geometric characteristic parameters of the ship type, including: main scale characteristic parameters of the ship type and propeller scale characteristic parameters;

[0018] The main scale parameters of the ship type include: ship design draft, ship vertical length, ship overall length, ship design waterline length, and ship type width;

[0019] Ship design draft (expressed as T d ): Obtained by inputting parameter value, unit: meter;

[0020] The length between perpendicular lines of the ship (expressed as L BP ): obtained by extracting the X-direction distance between the intersection of the bow and the design waterline and the stern perpendicular of the ship, in meters;

[0021] Ship design waterline length (expressed as L WL ): Extract the ship's design waterline based on the ship's design draft, and obtain it by reading the distance between the front and rear ends of the design waterline along the X direction, in meters;

[0022] Ship breadth (expressed as B): obtained by extracting the maximum distance between the intersection of the starboard and port surfaces of the ship and the midline surface of the ship in the Y direction, in meters;

[0023] The propeller scale characteristic parameters include: propeller diameter, propeller shaft height, distance between the propeller disk and the stern vertical line, distance between the propeller blade tip and the bottom of the ship, maximum X-coordinate of the propeller blade, minimum X-coordinate of the propeller blade, and minimum distance between the propeller blade and the rudder blade in the X direction.

[0024] Among them, the propeller diameter (denoted as D p ), propeller shaft height (i.e. the propeller shaft height from the baseline, expressed as H S ), the distance between the propeller disk and the stern perpendicular (expressed as X P ) and other parameters are obtained by inputting parameter values, and the unit is meter.

[0025] Distance between propeller blade and bottom of ship (D S ): Extract the midship longitudinal section line of the ship and x = X P The Z coordinate value of the intersection point of the plane (expressed as Z P ), D is calculated by the following formula S =Z P -(D p / 2+H S ).

[0026] The maximum X coordinate of the propeller blade (expressed as X Pmax ) and the minimum X coordinate of the propeller blade (denoted as X Pmin ): Establish a section at intervals of 0.01 meters along the Y direction, obtain the intersection line between the section and the propeller series, and extract the maximum X coordinate value of the intersection line to obtain the X Pmax value, the minimum X coordinate value is X Pmin value.

[0027] The minimum distance between the propeller blade and the rudder blade in the X direction (expressed as X RPmin ): Extract the Z direction plane Z=(D p / 2+H S )The maximum X coordinate value of the intersection line between the plane and the rudder (expressed as X Rmax ), X is calculated by the following formula RPmin Value: X RPmin =X Pmin -X RPmin .

[0028] The unit of this parameter is the length unit "meter"

[0029] Step 1.3: Extracting automated ship form characteristic parameters: using the three-dimensional geometric characteristic parameters of the ship form in step 1.2 as automated ship form characteristic parameters; constructing an automated ship form characteristic parameter extraction program based on steps 1.1-1.2, with the input being the sample ship form three-dimensional geometric model file, and the output being the automated ship form characteristic parameters.

[0030] Preferably, the method for establishing the numerical calculation domain of the self-propulsion performance of medium- and high-speed ships in step 1 is:

[0031] Step 1.4: Construct a fixed global coordinate system based on the model coordinate origin described in step 1.1 as input parameters;

[0032] Step 1.5: Obtain the coordinates of the ship's center of gravity in the global coordinate system (X G ,Y G ,Z G ), and use this as the coordinate origin to construct a hull motion coordinate system that moves with the hull, with the initial direction of the coordinate axis being that the X-axis direction points to the bow, the Y-axis direction points to the port side of the hull, and the Z-axis direction is vertically upward. The hull motion coordinate system is rigidly connected to the hull and moves synchronously with the hull;

[0033] Step 1.6: Based on the propeller shaft height (i.e. the propeller shaft height from the baseline, denoted as H S ), the distance between the propeller disk and the stern perpendicular (expressed as X P ) and other parameters, and obtain the coordinate value of the propeller center point in the hull motion coordinate system (X G -X P ,0,H S -Z G ), a propeller rotating coordinate system is constructed with the propeller center point as the coordinate origin. The propeller rotating coordinate system is rigidly connected to the hull and moves synchronously with the hull;

[0034] Step 1.7: Based on the automated ship form characteristic parameters and the global coordinate system, the hull motion coordinate system and the propeller rotation coordinate system, an internal calculation domain wrapping the hull, an external background calculation domain and a propeller rotation calculation domain are constructed.

[0035] Preferably, the method of constructing the internal calculation domain wrapping the hull, the external background calculation domain and the propeller rotation calculation domain in step 1.7 is:

[0036] Step 1.7.1: Establish an internal computational domain that wraps the hull: The scale is set to the parameters associated with the hull support, and the vertical motion and rotational motion around the Y axis of the hull are opened for numerical calculation based on the trim and heave motion of the ship during navigation. The internal and external computational domains use the overlapping grid method to transfer the flow field data information;

[0037] Step 1.7.2: Establish an external background calculation domain: The shape of the external background calculation domain is set to a rectangle to avoid the interference effect of the pool wall during the calculation process. The scale of the external background calculation domain is set to the parameters associated with the main scale of the hull and remains stationary during the calculation process;

[0038] Step 1.7.3: Establish propeller rotation calculation domain: The propeller rotation calculation domain is arranged at the stern shaft of the ship, and the propeller is wrapped in a cylinder. The axis of the cylinder is consistent with the propeller axis, and the scale of the cylinder is established in step 1.2 to associate the extracted hull parameters with the propeller scale characteristic parameters.

[0039] Preferably, in step 2.2, the step of establishing the automatic control method includes:

[0040] Step 2.2.1: Set the numerical solution convergence control process and divide the calculation process: the numerical solution convergence control process is the process from the completion of the calculation domain flow field initialization to the convergence of the numerical calculation of the propeller coupling under the multi-degree-of-freedom motion of the hull; the calculation process includes: the flow field initialization stage, the hull flow field preliminary calculation stage, the propeller coupling flow field numerical calculation stage, the hull motion superimposed propeller rotation flow field calculation stage, the refined numerical simulation stage, and the ship self-propulsion point calculation and ship self-propulsion performance analysis stage;

[0041] Step 2.2.2: Set the flow field initialization stage solution control method:

[0042] The initial conditions of the CFD numerical calculation model for the self-propulsion performance of high-speed ships in this stage are set as follows: the propeller speed is set to 0, and the freedom of the hull movement is locked, that is, the hull and propeller are both fixed constraint models, and the propeller is actually a fixed component rigidly connected to the hull, and the rotation speed is not given;

[0043] Input the ship speed into the CFD numerical calculation model of the medium- and high-speed ship self-propulsion performance in step 2.1 to solve the initialization flow field; the initialization flow field includes: the ship's initial speed and pressure parameters;

[0044] Step 2.2.3: Set the control method for solving the preliminary calculation stage of the hull flow field:

[0045] The initialized flow field is used as the initial condition of the CFD numerical calculation model of the self-propulsion performance of the high-speed ship in this stage. The time step is calculated based on the minimum grid size. At the same time, the freedom of the hull movement and the propeller rotation are continuously locked. The flow field near the hull is numerically iterated to solve the preliminary hull flow field; a curve for monitoring the change of hull resistance over time, namely the hull resistance curve, is established, and the curve is converged. If the convergence judgment condition is met, the next step is entered, and the preliminary hull flow field and hull resistance curve are output;

[0046] Step 2.2.4: Control method for numerical calculation of propeller-coupled flow field:

[0047] Based on the preliminary hull flow field as the initial condition of the CFD numerical calculation model of the self-propulsion performance of the medium- and high-speed ship in this stage, the propeller speed is set to solve the ship-propeller coupled flow field and perform convergence judgment;

[0048] A1: Solve the propeller coupled flow field: lock the hull motion freedom, use the motion reference coordinate system method to calculate the propeller rotation effect, calculate the time step based on the minimum grid size, and set the propeller speed to the initial speed n o ; Solve the propeller-paddle coupled flow field under the action of propeller suction;

[0049] A2: Convergence judgment: monitor and analyze the hull resistance, propeller thrust and propeller torque time history curves during the numerical calculation stage of the ship-propeller coupled flow field to see whether the convergence judgment conditions are met. If so, proceed to step 2.2.5; and output the force conditions of the propeller;

[0050] Step 2.2.5: Solution control method for the stage of calculating the flow field of hull motion superimposed on propeller rotation: Based on the ship-propeller coupled flow field as the initial condition of the CFD numerical calculation model of the self-propulsion performance of high-speed ships in this stage, the hull motion superimposed on the propeller rotation flow field is calculated and convergence judgment is performed;

[0051] B1: Solve the flow field of hull motion superimposed on propeller rotation: open the hull's degrees of freedom, use the motion reference coordinate system method to calculate the effect of propeller rotation, use the propeller speed to get the initial speed n0 calculated in step 2.2.4, calculate the time step based on the minimum grid size, and solve the flow field value of hull motion superimposed on propeller rotation;

[0052] B2: Convergence judgment: During the calculation process, monitor the time history curves of the hull resistance, propeller thrust, propeller torque, hull trim value, and hull sinking over time, analyze and judge the convergence of the time history curves, and calculate the changes in the ship's navigation attitude and the force on the propeller under the action of the ship-propeller coupling. After reaching convergence, proceed to step 2.2.6;

[0053] Step 2.2.6: Solve the control method in the refined numerical simulation stage: Based on the convergence conditions satisfied by the calculation in step 2.2.5, carry out refined numerical simulation of propeller-coupled multi-degree-of-freedom motion;

[0054] C1: The hull motion superimposed propeller rotation flow field is used as the initial condition of the CFD numerical calculation model of the self-propulsion performance of the high-speed ship in this stage. The hull degree of freedom is opened, and the sliding grid method is used to calculate the real rotation of the propeller. The propeller speed is set to the initial speed n0, and the time step is calculated using formula (1);

[0055]

[0056] Wherein, in formula (1), n ​​is the initial speed n0, a is the propeller rotation angle control parameter in each time step, and its value ranges from 1 to 2;

[0057] C2: Convergence judgment: monitor and analyze the time history curves of hull resistance, propeller thrust, propeller torque, hull trim value and hull sinking value in this stage respectively, and make convergence judgment. The overall mean value of the monitored values ​​calculated after the corresponding time history curve meets the convergence judgment conditions is taken as the corresponding hull resistance R′ under the initial speed n0 condition. 0B , propeller thrust T 0B and propeller torque Q 0B , hull trim value, hull sinking amount;

[0058] Step 2.2.7: Calculation and solution of the ship's self-propulsion point control method: Based on the initial speed n0 calculated in step 2.2.6, the corresponding hull resistance R′ 0B , propeller thrust T 0B , propeller torque Q 0B , hull trim value, hull sinking amount; according to formula (2), determine the force balance relationship of the oar;

[0059] ΔZ=T 0B -R′ 0B (2)

[0060] When ΔZ = 0, the propeller speed n0 is the ship's self-propulsion speed n B , and the corresponding R′ 0B , T 0B , Q 0B are respectively the hull resistance R at the self-propulsion point B , propeller thrust T B , propeller torque T B Calculate the result data; when ΔZ≠0, reselect the propeller speed and return to step 2.2.6 to calculate until ΔZ=0;

[0061] Step 2.2.8: Ship self-propulsion performance prediction method: Calculate the actual ship propeller received power P D ;

[0062] P D =2*π*n B *Q B (3)

[0063] The ship's self-propelled speed n B , propeller torque Q B .

[0064] Preferably, the convergence determination method is:

[0065] S1: Based on formulas (4) to (7), the amplitude, amplitude mean and overall mean of the monitored values ​​of the ship's resistance, propeller thrust, propeller torque, ship's trim value and ship's sinking time history curve within the set oscillation period are calculated respectively;

[0066] A i =R Pi -R Ti (4)

[0067]

[0068] Among them, A i , R Pi , R Ti They represent the amplitude, peak and trough of the i-th oscillation cycle of the curve respectively. It represents the mean amplitude of the 10 selected oscillation cycles;

[0069] The mean is calculated using formula (6) and formula (7);

[0070]

[0071] Among them, R 0i , R0 represent the mean value of the i-th oscillation period of the curve and the overall mean value of the monitoring quantity in all 10 oscillation periods respectively;

[0072] S2: Based on formulas (8) to (9), the convergence judgment conditions of the time history curves of hull resistance, propeller thrust, propeller torque, hull trim value and hull sinking value are calculated.

[0073]

[0074] Formula (8) is the ratio of the amplitude mean of the latest 10 change cycles of the time history curve to the overall mean of the monitored quantity is less than ε1, and ε1 is 5%;

[0075]

[0076] Formula (9) is that the percentage of the difference between the maximum value of the mean of the monitored quantity in each period of the time history curve and the overall mean is less than ε2, and ε2 is 1% to 2%;

[0077] When all the time history curves obtained in this stage meet the convergence judgment conditions at the same time, the calculation is judged to have reached convergence, and the overall mean values ​​of the monitored values ​​calculated after the time history curves of hull resistance, propeller thrust, propeller torque, hull trim value, and hull sinking meet the convergence judgment conditions are respectively used as the hull resistance R′ corresponding to the initial speed n0 condition. 0B , propeller thrust T 0B and propeller torque Q 0B , hull trim value, hull sinking amount; the calculation process enters the next step.

[0078] Preferably, the method for calculating the time step based on the minimum grid size is:

[0079]

[0080] Among them, Δt is the time step; is the reference velocity, which is taken as the incoming flow velocity in the computational domain; Δx is the minimum grid size in the flow direction, i.e., the x direction; C MAX is the Courant number, which is set to 10.

[0081] Preferably, the initial speed n in A1 o The calculation method is:

[0082] A11: Estimate the initial thrust T0 of the ship according to formula (11);

[0083]

[0084] Where R0 is the overall mean value of the monitored quantity calculated based on the time history curve of the hull resistance, that is, the mean value of the ship resistance; t is the thrust reduction fraction, which ranges from 0.15 to 0.25 depending on the ship type;

[0085] A12: Obtaining corresponding propeller open water characteristic data based on the ship type: the propeller open water characteristic data includes: the thrust coefficient K corresponding to the series advance coefficient J T , Torque coefficient K Q and open water efficiency η0 data;

[0086] A121: Get thrust coefficient K T0 : Based on 75% of the maximum open water efficiency as input, interpolation is performed on the propeller open water characteristic data curve to obtain the thrust coefficient K T0 ;

[0087] A13: Estimate the initial propeller speed n according to formula (12) o :

[0088]

[0089] Where ρ is the density of seawater and D is the propeller diameter.

[0090] Preferably, in step 2.2.7, when ΔZ≠0, the processing method is:

[0091] 1) If ΔZ < 0, it means that the thrust from the propeller cannot overcome the resistance of the hull, and the propeller speed needs to be increased. The new speeds n1, n2, and n3 are calculated using formulas (13) to (16), where K T0B The propeller thrust coefficient corresponding to the speed n0, ρ is the density of seawater, and D is the propeller diameter;

[0092]

[0093] n2=n1+(n1-n0) (15)

[0094] n3=n2+(n1-n0) (16)

[0095] Return to step 2.2.6, adjust the propeller speed to n1, n2, and n3 respectively, perform convergence judgment, and obtain the corresponding hull resistance R′ when the propeller speed is n1, n2, and n3 respectively. 1B , R′ 1B , R′ 1B Propeller thrust T 2B , T 2B , T 2B and propeller torque Q 3B , Q 3B , Q 3B At the same time, based on formula (2), the corresponding ΔZ1, ΔZ2, and ΔZ3 at three speeds are calculated; the hull resistance, propeller thrust, and propeller torque data at four speeds n0, n1, n2, and n3 are used, and ΔZ=0 is used as the input condition to perform cubic spline interpolation to obtain the propeller speed n that satisfies the condition of ΔZ=0. B 、Hull resistance R B , propeller thrust T B , propeller torque Q B ;

[0096] 2) If ΔZ>0, it means that the thrust of the propeller is too large and the propeller speed needs to be reduced. The new speeds n1, n2, and n3 are calculated using formulas (13) to (16), where K T0B The propeller thrust coefficient corresponding to the speed n0, ρ is the density of fresh water, and D is the propeller diameter;

[0097]

[0098] n2=n1-(n0-n1) (15)

[0099] n3=n2-(n0-n1) (16)

[0100] The propeller speeds are adjusted to n1, n2, and n3 respectively, and the refined numerical simulation of ship self-propulsion is carried out using step 2.2.6, and the convergence conditions are reached, and the corresponding hull resistance R′ is obtained under the propeller speeds n1, n2, and n3 respectively. 1B , R′ 1B , R′ 1B Propeller thrust T 2B , T 2B , T 2B and torque Q 3B , Q 3B , Q 3B, and based on formula (12), the corresponding ΔZ1, ΔZ2, and ΔZ3 at three speeds are calculated; with the series data corresponding to the four speeds n0, n1, n2, and n3, cubic spline interpolation is performed with ΔZ=0 as the input condition to obtain the propeller speed n that satisfies the condition ΔZ=0 B 、Hull resistance R B , propeller thrust T B , propeller torque Q B .

[0101] Preferably, the method for obtaining the three-dimensional geometric model file after the ship shape is deformed in step 3.1 is: using parametric modeling software to establish a parametric deformation model of the ship's stern, based on the hull deformation constraint conditions, changing the deformation parameters of the hull stern, realizing the three-dimensional geometric model transformation of the stern, and obtaining the three-dimensional geometric model file after the ship shape is deformed.

[0102] A system for evaluating and optimizing the propulsion performance of medium and high-speed ships.

[0103] Ship type transformation subsystem: including: a ship tail deformation unit for establishing a ship tail parametric deformation model based on parametric modeling software; a ship type deformation parameter acquisition unit for changing the deformation parameters of the hull tail to achieve the transformation of the stern three-dimensional geometric model, and obtaining the three-dimensional geometric model file after the ship type deformation as the sample ship type three-dimensional geometric model file;

[0104] The self-propulsion performance evaluation subsystem includes: a calculation domain unit for establishing a numerical calculation domain for the self-propulsion performance of a medium-high-speed ship; a medium-high-speed ship self-propulsion performance CFD numerical calculation model unit for conditionally configuring the medium-high-speed ship self-propulsion performance numerical calculation domain and establishing a medium-high-speed ship self-propulsion performance CFD numerical calculation model; a model control unit for establishing an automatic control method for the medium-high-speed ship self-propulsion performance CFD numerical calculation model; a ship self-propulsion performance numerical calculation model unit for establishing a medium-high-speed ship self-propulsion performance numerical calculation model in combination with the medium-high-speed ship self-propulsion performance CFD numerical calculation model and the automatic control method; a model calculation unit for inputting a sample ship three-dimensional geometric model file obtained by the ship transformation subsystem into the medium-high-speed ship self-propulsion performance numerical calculation model and calculating the power received by the ship propeller;

[0105] Medium and high-speed ship self-propulsion performance optimization subsystem: including: a condition preset unit for setting the ship self-propulsion performance optimization target as the genetic algorithm termination condition, and a self-propulsion performance optimization unit based on the ship propeller received power obtained by optimizing the self-propulsion performance evaluation subsystem based on the genetic algorithm.

[0106] The beneficial effects of the present invention are:

[0107] The present invention provides a method and system for evaluating and optimizing the propulsion performance of medium- and high-speed ships. Specifically, the method includes: a method for constructing a numerical calculation model for the self-propulsion performance of high-speed ships, a method for controlling and integrating the numerical calculation process for the propulsion performance of medium- and high-speed ships, and realizing the automatic construction of the numerical calculation model for self-propulsion of ships through the extraction and analysis of ship type characteristics, dividing the process for the evolution process of the self-propulsion calculation flow field, and adopting a step-by-step progressive method for the numerical calculation process to establish a calculation control method for each stage and a quantitative standard method for judging the calculation convergence, gradually approaching the real flow field conditions to achieve calculation convergence, and developing a calculation integration system for integrated packaging of the calculation process, on the one hand, avoiding the increase in the number of calculation iterations caused by the use of multi-stage coupled motion and too small time step from the beginning of the calculation, and the problem of slow convergence of calculation oscillation caused by the large difference between the initialization flow field and the actual flow field, and on the other hand, through the establishment of an integrated method and the development of an integrated system, the automation of the calculation process is realized, eliminating the requirement for manual control in the calculation process, and improving the calculation efficiency.

[0108] The present invention provides an integrated method and system for optimizing the self-propulsion performance of high-speed ships, establishes a propeller multi-speed adjustment method in self-propulsion calculation, a calculation convergence judgment standard, a calculation result extraction and a ship self-propulsion performance prediction method, establishes a ship self-propulsion performance automatic analysis process method, constructs an optimized method-driven medium- and high-speed ship type transformation, a self-propulsion performance evaluation process and an optimization design process method, solves the problem that manual interaction is required in the process and the full process automation cannot be achieved, and improves the application effect of optimization theory in the optimization design of medium- and high-speed ships. BRIEF DESCRIPTION OF THE DRAWINGS

[0109] Figure 1 It is a flow chart of the method for evaluating and optimizing the propulsion performance of high-speed ships in the present invention.

[0110] Figure 2 It is a flow chart of the method for constructing a numerical calculation domain for the self-propulsion performance of a medium- and high-speed ship according to the present invention.

[0111] Figure 3 The invention is a flow chart for controlling the numerical solution process of a medium- and high-speed ship.

[0112] Figure 4 It is a structural diagram of the high-speed ship propulsion performance evaluation and optimization design system in the present invention. Specific implementation methods

[0114] The present invention will be described below in conjunction with the accompanying drawings.

[0115] like Figure 1 As shown, a method for evaluating and optimizing the propulsion performance of a medium- and high-speed ship type comprises the following steps:

[0116] Step 1: Establishing the numerical calculation domain of the self-propulsion performance of medium- and high-speed ships: Obtain the sample ship three-dimensional geometric model file, extract the automated ship characteristic parameters; construct a coordinate system group based on the automated ship characteristic parameters and navigation parameters; the coordinate system group includes a global coordinate system, a hull motion coordinate system, and a propeller rotation coordinate system; based on the coordinate system group and the automated ship characteristic parameters, establish the numerical calculation domain of the self-propulsion performance of medium- and high-speed ships:

[0117] Step 2: Establish an integrated method for the numerical calculation process of medium- and high-speed ship self-propulsion performance;

[0118] Step 2.1: Establish a CFD numerical calculation model for the self-propulsion performance of medium- and high-speed ships by conditionally configuring the numerical calculation domain of the self-propulsion performance of medium- and high-speed ships in step 1: The conditional configuration includes: selecting the Reynolds average viscous flow calculation method as the basic method for solving the model, selecting the SST Kw turbulence model and the standard wall function to handle the ship-propeller coupled flow field simulation, selecting the VOF method to calculate the free liquid surface of the ship, using the method of alternating the motion reference coordinate system and the sliding grid to simulate the rotation of the propeller, and selecting the overlapping grid method to calculate the hull pitch and heave freedom movement;

[0119] Step 2.2: Establish an automatic control method for the CFD numerical calculation model of the self-propulsion performance of the medium- and high-speed ship described in step 2.1: 1) Set the numerical solution convergence control process and divide the calculation process: the calculation process includes the flow field initialization stage, the hull flow field preliminary calculation stage, the propeller coupling flow field numerical calculation stage, the hull motion superimposed propeller rotation flow field calculation stage, the refined numerical simulation stage, and the ship self-propulsion point calculation and ship self-propulsion performance analysis stage; 2) Formulate the solution control method and convergence judgment method for the hull flow field preliminary calculation stage, the propeller coupling flow field numerical calculation stage, the hull motion superimposed propeller rotation flow field calculation stage and the refined numerical simulation stage in sequence;

[0120] Step 2.3: Calculate the propeller received power: Combine the medium-high speed ship self-propulsion performance CFD numerical calculation model described in step 2.1 and the automatic control method of the model calculation process established in step 2.2 to establish a medium-high speed ship self-propulsion performance numerical calculation model, input the sample ship type three-dimensional geometric model file obtained in step 1, complete the medium-high speed ship self-propulsion point acquisition and ship self-propulsion performance characteristic parameter calculation and analysis, and output the propeller received power as the ship self-propulsion performance characteristic quantity;

[0121] Step 3: Establish a method for optimizing the self-propulsion performance of medium- and high-speed ships:

[0122] Step 3.1: Construct a 3D geometric model file of the deformed ship based on the hull deformation constraint conditions, and input it as a sample 3D geometric model file into step 2 to calculate the received power P of the ship propeller. D, to realize the numerical calculation of the self-propulsion performance of the modified ship type;

[0123] Step 3.2: Use genetic algorithm to optimize step 3.1 to obtain the power P received by the ship propeller D , taking the tail deformation parameter as the independent variable, the calculated ship propeller received power as the objective function, and the ship type optimization design target P D The value required is used as the optimization target of the ship's self-propulsion performance, that is, the preset termination condition of the genetic algorithm; the ship propeller receives the power P after automatic output optimization D .

[0124] like Figure 2 As shown in Figure 1, the specific steps for establishing the numerical calculation domain of the self-propulsion performance of medium- and high-speed ships in step 1 are:

[0125] Preferably, the method for extracting the automated ship type characteristic parameters in step 1 is:

[0126] Step 1.1: Obtain the sample ship type 3D geometric model file (IGS / IGES format). The length unit of the 3D model file is "meter". The origin of the model coordinate is located at the intersection of the ship's stern perpendicular and the ship's baseline. The X-axis direction of the coordinate system is from the stern to the bow, the Y-axis direction is from the starboard side to the port side, and the Z-axis direction is from the bottom of the ship to the vertical upward direction of the deck;

[0127] Step 1.2: Extracting three-dimensional geometric characteristic parameters of the ship type: Based on the sample three-dimensional geometric model file of the ship type described in step 1.1, extracting three-dimensional geometric characteristic parameters of the ship type, including: main scale characteristic parameters of the ship type and propeller scale characteristic parameters;

[0128] The main scale parameters of the ship type include: ship design draft, ship vertical length, ship overall length, ship design waterline length, and ship type width;

[0129] Ship design draft (expressed as T d ): Obtained by inputting parameter value, unit: meter;

[0130] The length between perpendicular lines of the ship (expressed as L BP ): obtained by extracting the X-direction distance between the intersection of the bow and the design waterline and the stern perpendicular of the ship, in meters;

[0131] Ship design waterline length (expressed as L WL ): Extract the ship's design waterline based on the ship's design draft, and obtain it by reading the distance between the front and rear ends of the design waterline along the X direction, in meters;

[0132] Ship breadth (expressed as B): obtained by extracting the maximum distance between the intersection of the starboard and port surfaces of the ship and the midline surface of the ship in the Y direction, in meters;

[0133] The propeller scale characteristic parameters include: propeller diameter, propeller shaft height, distance between the propeller disk and the stern vertical line, distance between the propeller blade tip and the bottom of the ship, maximum X-coordinate of the propeller blade, minimum X-coordinate of the propeller blade, and minimum distance between the propeller blade and the rudder blade in the X direction.

[0134] Among them, the propeller diameter (denoted as D p ), propeller shaft height (i.e. the propeller shaft height from the baseline, expressed as H S ), the distance between the propeller disk and the stern perpendicular (expressed as X P ) and other parameters are obtained by inputting parameter values, and the unit is meter.

[0135] Distance between propeller blade and bottom of ship (D S ): Extract the midship longitudinal section line of the ship and x = X P The Z coordinate value of the intersection point of the plane (expressed as Z P ), D is calculated by the following formula S =Z P -(D p / 2+H S ).

[0136] The maximum X coordinate of the propeller blade (expressed as X Pmax ) and the minimum X coordinate of the propeller blade (denoted as X Pmin ): Establish a section at intervals of 0.01 meters along the Y direction, obtain the intersection line between the section and the propeller series, and extract the maximum X coordinate value of the intersection line to obtain the X Pmax value, the minimum X coordinate value is X Pmin value.

[0137] The minimum distance between the propeller blade and the rudder blade in the X direction (expressed as X RPmin ): Extract the Z direction plane Z=(D p / 2+H S )The maximum X coordinate value of the intersection line between the plane and the rudder (expressed as X Rmax ), X is calculated by the following formula RPmin Value: X RPmin =X Pmin -X RPmin .

[0138] The unit of this parameter is the length unit "meter"

[0139] Step 1.3: Extracting automated ship form characteristic parameters: using the three-dimensional geometric characteristic parameters of the ship form in step 1.2 as automated ship form characteristic parameters; constructing an automated ship form characteristic parameter extraction program based on steps 1.1-1.2, with the input being the sample ship form three-dimensional geometric model file, and the output being the automated ship form characteristic parameters.

[0140] Preferably, the method for establishing the numerical calculation domain of the self-propulsion performance of medium- and high-speed ships in step 1 is:

[0141] Step 1.4: Construct a fixed global coordinate system based on the model coordinate origin described in step 1.1 as input parameters;

[0142] Step 1.5: Obtain the coordinates of the ship's center of gravity in the global coordinate system (X G ,Y G ,Z G ), and use this as the coordinate origin to construct a hull motion coordinate system that moves with the hull, with the initial direction of the coordinate axis being that the X-axis direction points to the bow, the Y-axis direction points to the port side of the hull, and the Z-axis direction is vertically upward. The hull motion coordinate system is rigidly connected to the hull and moves synchronously with the hull;

[0143] Step 1.6: Based on the propeller shaft height (i.e. the propeller shaft height from the baseline, denoted as H S ), the distance between the propeller disk and the stern perpendicular (expressed as X P ) and other parameters, and obtain the coordinate value of the propeller center point in the hull motion coordinate system (X G -X P ,0,H S -Z G ), a propeller rotating coordinate system is constructed with the propeller center point as the coordinate origin. The propeller rotating coordinate system is rigidly connected to the hull and moves synchronously with the hull;

[0144] Step 1.7: Based on the automated ship form characteristic parameters and the global coordinate system, the hull motion coordinate system and the propeller rotation coordinate system, an internal calculation domain wrapping the hull, an external background calculation domain and a propeller rotation calculation domain are constructed.

[0145] Preferably, the method of constructing the internal calculation domain wrapping the hull, the external background calculation domain and the propeller rotation calculation domain in step 1.7 is:

[0146] Step 1.7.1: Establish an internal computational domain that wraps the hull: The scale is set to the parameters associated with the hull support, and the vertical motion and rotational motion around the Y axis of the hull are opened for numerical calculation based on the trim and heave motion of the ship during navigation. The internal and external computational domains use the overlapping grid method to transfer the flow field data information;

[0147] Step 1.7.2: Establish an external background calculation domain: The shape of the external background calculation domain is set to a rectangle to avoid the interference effect of the pool wall during the calculation process. The scale of the external background calculation domain is set to the parameters associated with the main scale of the hull and remains stationary during the calculation process;

[0148] Step 1.7.3: Establish propeller rotation calculation domain: The propeller rotation calculation domain is arranged at the stern shaft of the ship, and the propeller is wrapped in a cylinder. The axis of the cylinder is consistent with the propeller axis, and the scale of the cylinder is established in step 1.2 to associate the extracted hull parameters with the propeller scale characteristic parameters.

[0149] Preferably, in step 2.2, the step of establishing the automatic control method includes:

[0150] Step 2.2.1: Set the numerical solution convergence control process and divide the calculation process: the numerical solution convergence control process is the process from the completion of the calculation domain flow field initialization to the convergence of the numerical calculation of the propeller coupling under the multi-degree-of-freedom motion of the hull; the calculation process includes: the flow field initialization stage, the hull flow field preliminary calculation stage, the propeller coupling flow field numerical calculation stage, the hull motion superimposed propeller rotation flow field calculation stage, the refined numerical simulation stage, and the ship self-propulsion point calculation and ship self-propulsion performance analysis stage;

[0151] like Figure 3 As shown, the specific steps of the calculation process described in step 2.2.1 are:

[0152] Step 2.2.2: Set the flow field initialization stage solution control method:

[0153] The initial conditions of the CFD numerical calculation model for the self-propulsion performance of high-speed ships in this stage are set as follows: the propeller speed is set to 0, and the freedom of the hull movement is locked, that is, the hull and propeller are both fixed constraint models, and the propeller is actually a fixed component rigidly connected to the hull, and the rotation speed is not given;

[0154] Input the ship speed into the CFD numerical calculation model of the medium- and high-speed ship self-propulsion performance in step 2.1 to solve the initialization flow field; the initialization flow field includes: the ship's initial speed and pressure parameters;

[0155] Step 2.2.3: Set the control method for solving the preliminary calculation stage of the hull flow field:

[0156] The initialized flow field is used as the initial condition of the CFD numerical calculation model of the self-propulsion performance of the high-speed ship in this stage. The time step is calculated based on the minimum grid size. At the same time, the freedom of the hull movement and the propeller rotation are continuously locked. The flow field near the hull is numerically iterated to solve the preliminary hull flow field; a curve for monitoring the change of hull resistance over time, namely the hull resistance curve, is established, and the curve is converged. If the convergence judgment condition is met, the next step is entered, and the preliminary hull flow field and hull resistance curve are output;

[0157] Step 2.2.4: Control method for numerical calculation of propeller-coupled flow field:

[0158] Based on the preliminary hull flow field as the initial condition of the CFD numerical calculation model of the self-propulsion performance of the medium- and high-speed ship in this stage, the propeller speed is set to solve the ship-propeller coupled flow field and perform convergence judgment;

[0159] A1: Solve the propeller coupled flow field: lock the hull motion freedom, use the motion reference coordinate system method to calculate the propeller rotation effect, calculate the time step based on the minimum grid size, and set the propeller speed to the initial speed n o ; Solve the propeller-paddle coupled flow field under the action of propeller suction;

[0160] A2: Convergence judgment: monitor and analyze the hull resistance, propeller thrust and propeller torque time history curves during the numerical calculation stage of the ship-propeller coupled flow field to see whether the convergence judgment conditions are met. If so, proceed to step 2.2.5; and output the force conditions of the propeller;

[0161] Step 2.2.5: Solution control method for the stage of calculating the flow field of hull motion superimposed on propeller rotation: Based on the ship-propeller coupled flow field as the initial condition of the CFD numerical calculation model of the self-propulsion performance of high-speed ships in this stage, the hull motion superimposed on the propeller rotation flow field is calculated and convergence judgment is performed;

[0162] B1: Solve the flow field of hull motion superimposed on propeller rotation: open the hull's degrees of freedom, use the motion reference coordinate system method to calculate the effect of propeller rotation, use the propeller speed to get the initial speed n0 calculated in step 2.2.4, calculate the time step based on the minimum grid size, and solve the flow field value of hull motion superimposed on propeller rotation;

[0163] B2: Convergence judgment: During the calculation process, monitor the time history curves of the hull resistance, propeller thrust, propeller torque, hull trim value, and hull sinking over time, analyze and judge the convergence of the time history curves, and calculate the changes in the ship's navigation attitude and the force on the propeller under the action of the ship-propeller coupling. After reaching convergence, proceed to step 2.2.6;

[0164] Step 2.2.6: Solve the control method in the refined numerical simulation stage: Based on the convergence conditions satisfied by the calculation in step 2.2.5, carry out refined numerical simulation of propeller-coupled multi-degree-of-freedom motion;

[0165] C1: The hull motion superimposed propeller rotation flow field is used as the initial condition of the CFD numerical calculation model of the self-propulsion performance of the high-speed ship in this stage. The hull degree of freedom is opened, and the sliding grid method is used to calculate the real rotation of the propeller. The propeller speed is set to the initial speed n0, and the time step is calculated using formula (1);

[0166]

[0167] Wherein, in formula (1), n ​​is the initial speed n0, a is the propeller rotation angle control parameter in each time step, and its value ranges from 1 to 2;

[0168] C2: Convergence judgment: monitor and analyze the time history curves of hull resistance, propeller thrust, propeller torque, hull trim value and hull sinking value in this stage respectively, and make convergence judgment. The overall mean value of the monitored values ​​calculated after the corresponding time history curve meets the convergence judgment conditions is taken as the corresponding hull resistance R′ under the initial speed n0 condition. 0B , propeller thrust T 0B and propeller torque Q 0B , hull trim value, hull sinking amount;

[0169] Step 2.2.7: Calculation and solution of the ship's self-propulsion point control method: Based on the initial speed n0 calculated in step 2.2.6, the corresponding hull resistance R′ 0B , propeller thrust T 0B , propeller torque Q 0B , hull trim value, hull sinking amount; according to formula (2), determine the force balance relationship of the oar;

[0170] ΔZ=T 0B -R′ 0B (2)

[0171] When ΔZ = 0, the propeller speed n0 is the ship's self-propulsion speed n B , and the corresponding R′ 0B , T 0B , Q 0B are respectively the hull resistance R at the self-propulsion point B , propeller thrust T B , propeller torque T B Calculate the result data; when ΔZ≠0, reselect the propeller speed and return to step 2.2.6 to calculate until ΔZ=0;

[0172] Step 2.2.8: Ship self-propulsion performance prediction method: Calculate the actual ship propeller received power P D ;

[0173] P D =2*π*n B *Q B (3)

[0174] The ship's self-propelled speed n B , propeller torque Q B .

[0175] Preferably, the convergence determination method is:

[0176] S1: Based on formulas (4) to (7), the amplitude, amplitude mean and overall mean of the monitored values ​​of the ship's resistance, propeller thrust, propeller torque, ship's trim value and ship's sinking time history curve within the set oscillation period are calculated respectively;

[0177] A i =R Pi -R Ti (4)

[0178]

[0179] Among them, A i , R Pi , R Ti They represent the amplitude, peak and trough of the i-th oscillation cycle of the curve respectively. It represents the mean amplitude of the 10 selected oscillation cycles;

[0180] The mean is calculated using formula (6) and formula (7);

[0181]

[0182] Among them, R 0i , R0 represent the mean value of the i-th oscillation period of the curve and the overall mean value of the monitoring quantity in all 10 oscillation periods respectively;

[0183] S2: Based on formulas (8) to (9), the convergence judgment conditions of the time history curves of hull resistance, propeller thrust, propeller torque, hull trim value and hull sinking value are calculated.

[0184]

[0185] Formula (8) is the ratio of the amplitude mean of the latest 10 change cycles of the time history curve to the overall mean of the monitored quantity is less than ε1, and ε1 is 5%;

[0186]

[0187] Formula (9) is that the percentage of the difference between the maximum value of the mean of the monitored quantity in each period of the time history curve and the overall mean is less than ε2, and ε2 is 1% to 2%;

[0188] When all the time history curves obtained in this stage meet the convergence judgment conditions at the same time, the calculation is judged to have reached convergence, and the overall mean values ​​of the monitored values ​​calculated after the time history curves of hull resistance, propeller thrust, propeller torque, hull trim value, and hull sinking meet the convergence judgment conditions are respectively used as the hull resistance R′ corresponding to the initial speed n0 condition. 0B , propeller thrust T 0B and propeller torque Q 0B, hull trim value, hull sinking amount; the calculation process enters the next step.

[0189] Preferably, the method for calculating the time step based on the minimum grid size is:

[0190]

[0191] Among them, Δt is the time step; is the reference velocity, which is taken as the incoming flow velocity in the computational domain; Δx is the minimum grid size in the flow direction, i.e., the x direction; C MAX is the Courant number, which is set to 10.

[0192] Preferably, the initial speed n in A1 is o The calculation method is:

[0193] A11: Estimate the initial thrust T0 of the ship according to formula (11);

[0194]

[0195] Where R0 is the overall mean value of the monitored quantity calculated based on the time history curve of the hull resistance, that is, the mean value of the ship resistance; t is the thrust reduction fraction, which ranges from 0.15 to 0.25 depending on the ship type;

[0196] A12: Obtaining corresponding propeller open water characteristic data based on the ship type: the propeller open water characteristic data includes: the thrust coefficient K corresponding to the series advance coefficient J T , Torque coefficient K Q and open water efficiency η0 data;

[0197] A121: Get thrust coefficient K T0 : Based on 75% of the maximum open water efficiency as input, interpolation is performed on the propeller open water characteristic data curve to obtain the thrust coefficient K T0 ;

[0198] A13: Estimate the initial propeller speed n according to formula (12) o :

[0199]

[0200] Where ρ is the density of seawater and D is the propeller diameter.

[0201] Preferably, in step 2.2.7, when ΔZ≠0, the processing method is:

[0202] 3) If ΔZ < 0, it means that the thrust from the propeller cannot overcome the resistance of the hull, and the propeller speed needs to be increased. The new speeds n1, n2, and n3 are calculated using formulas (13) to (16), where K T0BThe propeller thrust coefficient corresponding to the speed n0, ρ is the density of seawater, and D is the propeller diameter;

[0203]

[0204] n2=n1+(n1-n0) (15)

[0205] n3=n2+(n1-n0) (16)

[0206] Return to step 2.2.6, adjust the propeller speed to n1, n2, and n3 respectively, perform convergence judgment, and obtain the corresponding hull resistance R′ when the propeller speed is n1, n2, and n3 respectively. 1B , R′ 1B , R′ 1B Propeller thrust T 2B , T 2B , T 2B and propeller torque Q 3B , Q 3B , Q 3B At the same time, based on formula (2), the corresponding ΔZ1, ΔZ2, and ΔZ3 at three speeds are calculated; the hull resistance, propeller thrust, and propeller torque data at four speeds n0, n1, n2, and n3 are used, and ΔZ=0 is used as the input condition to perform cubic spline interpolation to obtain the propeller speed n that satisfies the condition of ΔZ=0. B 、Hull resistance R B , propeller thrust T B , propeller torque Q B ;

[0207] 4) If ΔZ>0, it means that the thrust of the propeller is too large and the propeller speed needs to be reduced. The new speeds n1, n2, and n3 are calculated using formulas (13) to (16), where K T0B The propeller thrust coefficient corresponding to the speed n0, ρ is the density of fresh water, and D is the propeller diameter;

[0208]

[0209] n2=n1-(n0-n1) (15)

[0210] n3=n2-(n0-n1) (16)

[0211] The propeller speeds are adjusted to n1, n2, and n3 respectively, and the refined numerical simulation of ship self-propulsion is carried out using step 2.2.6, and the convergence conditions are reached, and the corresponding hull resistance R′ is obtained under the propeller speeds n1, n2, and n3 respectively. 1B , R′ 1B , R′ 1B Propeller thrust T 2B, T 2B , T 2B and torque Q 3B , Q 3B , Q 3B , and based on formula (12), the corresponding ΔZ1, ΔZ2, and ΔZ3 at three speeds are calculated; with the series data corresponding to the four speeds n0, n1, n2, and n3, cubic spline interpolation is performed with ΔZ=0 as the input condition to obtain the propeller speed n that satisfies the condition ΔZ=0 B 、Hull resistance R B , propeller thrust T B , propeller torque Q B .

[0212] Preferably, the method for obtaining the three-dimensional geometric model file after the ship shape is deformed in step 3.1 is: using parametric modeling software to establish a parametric deformation model of the ship's stern, based on the hull deformation constraint conditions, changing the deformation parameters of the hull stern, realizing the three-dimensional geometric model transformation of the stern, and obtaining the three-dimensional geometric model file after the ship shape is deformed.

[0213] like Figure 4 As shown in the figure, a system for evaluating and optimizing the propulsion performance of medium and high-speed ships is proposed.

[0214] Ship type transformation subsystem: including: a ship tail deformation unit for establishing a ship tail parametric deformation model based on parametric modeling software; a ship type deformation parameter acquisition unit for changing the deformation parameters of the hull tail to achieve the transformation of the stern three-dimensional geometric model, and obtaining the three-dimensional geometric model file after the ship type deformation as the sample ship type three-dimensional geometric model file;

[0215] The self-propulsion performance evaluation subsystem includes: a calculation domain unit for establishing a numerical calculation domain for the self-propulsion performance of a medium-high-speed ship; a medium-high-speed ship self-propulsion performance CFD numerical calculation model unit for conditionally configuring the medium-high-speed ship self-propulsion performance numerical calculation domain and establishing a medium-high-speed ship self-propulsion performance CFD numerical calculation model; a model control unit for establishing an automatic control method for the medium-high-speed ship self-propulsion performance CFD numerical calculation model; a ship self-propulsion performance numerical calculation model unit for establishing a medium-high-speed ship self-propulsion performance numerical calculation model in combination with the medium-high-speed ship self-propulsion performance CFD numerical calculation model and the automatic control method; a model calculation unit for inputting a sample ship three-dimensional geometric model file obtained by the ship transformation subsystem into the medium-high-speed ship self-propulsion performance numerical calculation model and calculating the power received by the ship propeller;

[0216] Medium and high-speed ship self-propulsion performance optimization subsystem: including: a condition preset unit for setting the ship self-propulsion performance optimization target as the genetic algorithm termination condition, and a self-propulsion performance optimization unit based on the ship propeller received power obtained by optimizing the self-propulsion performance evaluation subsystem based on the genetic algorithm.

[0217] It should be noted that the above-described specific implementations can enable those skilled in the art to more fully understand the invention, but do not limit the invention in any way. Therefore, although this specification has described the invention in detail with reference to the drawings and embodiments, those skilled in the art should understand that the invention can still be modified or replaced by equivalents. In short, all technical solutions and improvements that do not deviate from the spirit and scope of the invention should be included in the protection scope of the patent for the invention.

Claims

1. A method for evaluating and optimizing the propulsion performance of medium- and high-speed ships, characterized in that: The following steps are involved: Step 1: Establishing the numerical calculation domain of the self-propulsion performance of medium- and high-speed ships: Obtain the sample ship three-dimensional geometric model file, extract the automated ship characteristic parameters; construct a coordinate system group based on the automated ship characteristic parameters and navigation parameters; the coordinate system group includes a global coordinate system, a hull motion coordinate system, and a propeller rotation coordinate system; based on the coordinate system group and the automated ship characteristic parameters, establish the numerical calculation domain of the self-propulsion performance of medium- and high-speed ships: Step 2: Establish an integrated method for the numerical calculation process of medium- and high-speed ship self-propulsion performance; Step 2.1: Establish a CFD numerical calculation model for the self-propulsion performance of medium- and high-speed ships by conditionally configuring the numerical calculation domain of the self-propulsion performance of medium- and high-speed ships in step 1: The conditional configuration includes: selecting the Reynolds average viscous flow calculation method as the basic method for solving the model, selecting the SST Kw turbulence model and the standard wall function to handle the ship-propeller coupled flow field simulation, selecting the VOF method to calculate the free liquid surface of the ship, using the method of alternating the motion reference coordinate system and the sliding grid to simulate the rotation of the propeller, and selecting the overlapping grid method to calculate the hull pitch and heave freedom movement; Step 2.2: Establish an automatic control method for the CFD numerical calculation model of the self-propulsion performance of the medium- and high-speed ship described in step 2.1: 1) Set the numerical solution convergence control process and divide the calculation process: the calculation process includes the flow field initialization stage, the hull flow field preliminary calculation stage, the propeller coupling flow field numerical calculation stage, the hull motion superimposed propeller rotation flow field calculation stage, the refined numerical simulation stage, and the ship self-propulsion point calculation and ship self-propulsion performance analysis stage; 2) Formulate the solution control method and convergence judgment method for the hull flow field preliminary calculation stage, the propeller coupling flow field numerical calculation stage, the hull motion superimposed propeller rotation flow field calculation stage and the refined numerical simulation stage in sequence; Step 2.3: Calculate the propeller received power: Combine the medium-high speed ship self-propulsion performance CFD numerical calculation model described in step 2.1 and the automatic control method of the model calculation process established in step 2.2 to establish a medium-high speed ship self-propulsion performance numerical calculation model, input the sample ship type three-dimensional geometric model file obtained in step 1, complete the medium-high speed ship self-propulsion point acquisition and ship self-propulsion performance characteristic parameter calculation and analysis, and output the propeller received power as the ship self-propulsion performance characteristic quantity; Step 3: Establish a method for optimizing the self-propulsion performance of medium- and high-speed ships: Step 3.1: Construct a 3D geometric model file of the deformed ship based on the hull deformation constraint conditions, and input it as a sample 3D geometric model file into step 2 to calculate the received power P of the ship propeller. D , to realize the numerical calculation of the self-propulsion performance of the modified ship type; Step 3.2: Use genetic algorithm to optimize step 3.1 to obtain the power P received by the ship propeller D , taking the tail deformation parameter as the independent variable, the calculated ship propeller received power as the objective function, and the ship type optimization design target P D The value required is used as the optimization target of the ship's self-propulsion performance, that is, the preset termination condition of the genetic algorithm; the ship propeller receives the power P after automatic output optimization D .

2. A method for evaluating and optimizing propulsion performance of medium- and high-speed ships according to claim 1, characterized in that: The method for extracting the automated ship type characteristic parameters in step 1 is: Step 1.1: Obtain the sample ship type 3D geometric model file (IGS / IGES format). The length unit of the 3D model file is "meter". The origin of the model coordinate is located at the intersection of the ship's stern vertical line and the ship's baseline. The X-axis direction of the coordinate system is from the stern to the bow, the Y-axis direction is from the starboard side to the port side of the ship, and the Z-axis direction is from the bottom of the ship to the vertical upward direction of the deck; Step 1.2: Extract the three-dimensional geometric feature parameters of the ship type: Based on the sample ship type 3D geometric model file described in step 1.1, extract the ship type 3D geometric characteristic parameters, including: ship type main scale characteristic parameters, propeller scale characteristic parameters; The main characteristic parameters of the ship type include: ship design draft, ship vertical length, ship overall length, ship design waterline length, and ship type width; Ship design draft (expressed as T d ): Get by inputting parameter value; The length between perpendicular lines of the ship (expressed as L BP ): obtained by extracting the X-direction distance between the intersection of the bow and the design waterline and the stern perpendicular of the ship, in meters; Ship design waterline length (expressed as L WL ): Extract the ship design waterline based on the ship design draft, and obtain it by reading the distance between the front and rear ends of the design waterline along the X direction, in meters; Ship breadth (expressed as B): obtained by extracting the maximum distance between the intersection of the starboard and port surfaces of the ship and the midline surface of the ship in the Y direction, in meters; The propeller scale characteristic parameters include: propeller diameter, propeller shaft height, distance between propeller disk and stern vertical line, distance between propeller blade tip and ship bottom, maximum X coordinate of propeller blade, minimum X coordinate of propeller blade, minimum distance between propeller blade and rudder blade in X direction; Among them, the propeller diameter (denoted as D p ), propeller shaft height (i.e. the propeller shaft height from the baseline, expressed as H S ), the distance between the propeller disk and the stern perpendicular (expressed as X P ) and other parameters are obtained by inputting parameter values; Distance between propeller blade and bottom of ship (D S ): Extract the midship longitudinal section line of the ship and x = X P The Z coordinate value of the intersection point of the plane (expressed as Z P ), D is calculated by the following formula s =Z p -(D p / 2+H s ); The maximum X coordinate of the propeller blade (expressed as X Pmax ) and the minimum X coordinate of the propeller blade (denoted as X Pmin ): Establish a section at intervals of 0.01 meters along the Y direction, obtain the intersection line between the section and the propeller series, and extract the maximum X coordinate value of the intersection line to obtain the X Pmax value, the minimum X coordinate value is X Pmin value; The minimum distance between the propeller blade and the rudder blade in the X direction (expressed as X RPmin ): Extract the Z direction plane Z=(D p / 2+H S )The maximum X coordinate value of the intersection line between the plane and the rudder (expressed as X Rmax ), and X is calculated by the following formula RPmin Value: X RPmin =X Pmin -X RPmin ; Step 1.3: Extracting automated ship form characteristic parameters: Using the three-dimensional geometric characteristic parameters of the ship form in step 1.2 as automated ship form characteristic parameters; constructing an automated ship form characteristic parameter extraction program based on steps 1.1-1.2, with the input being the sample ship form three-dimensional geometric model file and the output being the automated ship form characteristic parameters.

3. A method for evaluating and optimizing the propulsion performance of a medium- and high-speed ship according to claim 2, characterized in that: The method for establishing the numerical calculation domain of the self-propulsion performance of medium- and high-speed ships in step 1 is: Step 1.4: Construct a fixed global coordinate system based on the model coordinate origin described in step 1.1 as input parameters; Step 1.5: Obtain the coordinates of the ship's center of gravity in the global coordinate system (X G ,Y G ,Z G ), and use this as the coordinate origin to construct a hull motion coordinate system that moves with the hull, with the initial direction of the coordinate axis being that the X-axis direction points to the bow, the Y-axis direction points to the port side of the hull, and the Z-axis direction is vertically upward. The hull motion coordinate system is rigidly connected to the hull and moves synchronously with the hull; Step 1.6: Based on the propeller shaft height (i.e. the propeller shaft height from the baseline, denoted as H S ), the distance between the propeller disk and the stern perpendicular (expressed as X P ) parameters, and obtain the coordinate value of the propeller center point in the hull motion coordinate system (X G -X P ,0,H S -Z G ), a propeller rotating coordinate system is constructed with the propeller center point as the coordinate origin. The propeller rotating coordinate system is rigidly connected to the hull and moves synchronously with the hull; Step 1.7: Based on the automated ship form characteristic parameters and the global coordinate system, the hull motion coordinate system and the propeller rotation coordinate system, an internal calculation domain wrapping the hull, an external background calculation domain and a propeller rotation calculation domain are constructed.

4. A method for evaluating and optimizing propulsion performance of medium- and high-speed ships according to claim 2, characterized in that: Step 1.7 The method for constructing the internal calculation domain that wraps the hull, the external background calculation domain, and the propeller rotation calculation domain is as follows: Step 1.7.1: Establish an internal computational domain that wraps the hull: The scale is set to the parameters associated with the hull support, and the vertical motion and rotational motion around the Y axis of the hull are opened for numerical calculation based on the trim and heave motion of the ship during navigation. The internal and external computational domains use the overlapping grid method to transfer the flow field data information; Step 1.7.2: Establish an external background calculation domain: The shape of the external background calculation domain is set to a rectangle to avoid the interference effect of the pool wall during the calculation process. The scale of the external background calculation domain is set to the parameters associated with the main scale of the hull and remains stationary during the calculation process; Step 1.7.3: Establish propeller rotation calculation domain: The propeller rotation calculation domain is arranged at the stern shaft of the ship, and the propeller is wrapped in a cylinder. The axis of the cylinder is consistent with the propeller axis, and the scale of the cylinder is established in step 1.2 to associate the extracted hull parameters with the propeller scale characteristic parameters.

5. A method for evaluating and optimizing propulsion performance of medium- and high-speed ships according to claim 1, characterized in that: In step 2.2, the steps of establishing the automatic control method include: Step 2.2.1: Set the numerical solution convergence control process and divide the calculation process: the numerical solution convergence control process is the process from the completion of the calculation domain flow field initialization to the convergence of the numerical calculation of the propeller coupling under the multi-degree-of-freedom motion of the hull; the calculation process includes: the flow field initialization stage, the hull flow field preliminary calculation stage, the propeller coupling flow field numerical calculation stage, the hull motion superimposed propeller rotation flow field calculation stage, the refined numerical simulation stage, and the ship self-propulsion point calculation and ship self-propulsion performance analysis stage; Step 2.2.2: Set the flow field initialization stage solution control method: The initial conditions of the CFD numerical calculation model for the self-propulsion performance of high-speed ships in this stage are set as follows: the propeller speed is set to 0, and the freedom of the hull movement is locked, that is, the hull and propeller are both fixed constraint models, and the propeller is actually a fixed component rigidly connected to the hull, and the rotation speed is not given; Input the ship speed into the CFD numerical calculation model of the medium- and high-speed ship self-propulsion performance in step 2.1 to solve the initialization flow field; the initialization flow field includes: the ship's initial speed and pressure parameters; Step 2.2.3: Set the control method for solving the preliminary calculation stage of the hull flow field: The initialized flow field is used as the initial condition of the CFD numerical calculation model of the self-propulsion performance of the high-speed ship in this stage. The time step is calculated based on the minimum grid size. At the same time, the freedom of the hull movement and the propeller rotation are continuously locked. The flow field near the hull is numerically iterated to solve the preliminary hull flow field; a curve for monitoring the change of hull resistance over time, namely the hull resistance curve, is established, and the curve is converged. If the convergence judgment condition is met, the next step is entered, and the preliminary hull flow field and hull resistance curve are output; Step 2.2.4: Control method for numerical calculation of propeller-coupled flow field: Based on the preliminary hull flow field as the initial condition of the CFD numerical calculation model of the self-propulsion performance of the medium- and high-speed ship in this stage, the propeller speed is set to solve the ship-propeller coupled flow field and perform convergence judgment; A1: Solve the propeller coupled flow field: lock the hull motion freedom, use the motion reference coordinate system method to calculate the propeller rotation effect, calculate the time step based on the minimum grid size, and set the propeller speed to the initial speed n o ; Solve the propeller-paddle coupled flow field under the action of propeller suction; A2: Convergence judgment: monitor and analyze the hull resistance, propeller thrust and propeller torque time history curves during the numerical calculation stage of the ship-propeller coupled flow field to see whether the convergence judgment conditions are met. If so, proceed to step 2.2.5; and output the force conditions of the propeller; Step 2.2.5: Solution control method for the stage of calculating the flow field of hull motion superimposed on propeller rotation: Based on the ship-propeller coupled flow field as the initial condition of the CFD numerical calculation model of the self-propulsion performance of high-speed ships in this stage, the hull motion superimposed on the propeller rotation flow field is calculated and convergence judgment is performed; B1: Solve the flow field of hull motion superimposed on propeller rotation: open the hull's degrees of freedom, use the motion reference coordinate system method to calculate the effect of propeller rotation, use the propeller speed to get the initial speed n0 calculated in step 2.2.4, calculate the time step based on the minimum grid size, and solve the flow field value of hull motion superimposed on propeller rotation; B2: Convergence judgment: During the calculation process, monitor the time history curves of the hull resistance, propeller thrust, propeller torque, hull trim value, and hull sinking over time, analyze and judge the convergence of the time history curves, and calculate the changes in the ship's navigation attitude and the force on the propeller under the action of the ship-propeller coupling. After reaching convergence, proceed to step 2.2.6; Step 2.2.6: Solve the control method in the refined numerical simulation stage: Based on the convergence conditions satisfied by the calculation in step 2.2.5, carry out refined numerical simulation of propeller-coupled multi-degree-of-freedom motion; C1: The hull motion superimposed propeller rotation flow field is used as the initial condition of the CFD numerical calculation model of the self-propulsion performance of the high-speed ship in this stage. The hull degree of freedom is opened, and the sliding grid method is used to calculate the real rotation of the propeller. The propeller speed is set to the initial speed n0, and the time step is calculated using formula (1); Wherein, in formula (1), n ​​is the initial speed n0, a is the propeller rotation angle control parameter in each time step, and its value ranges from 1 to 2; C2: Convergence judgment: monitor and analyze the time history curves of hull resistance, propeller thrust, propeller torque, hull trim value and hull sinking value in this stage respectively, and make convergence judgment. The overall mean value of the monitored values ​​calculated after the corresponding time history curve meets the convergence judgment conditions is taken as the corresponding hull resistance R′ under the initial speed n0 condition. 0B , propeller thrust T 0B and propeller torque Q 0B , hull trim value, hull sinking amount; Step 2.2.7: Calculation and solution of the ship's self-propulsion point control method: Based on the initial speed n0 calculated in step 2.2.6, the corresponding hull resistance R′ 0B , propeller thrust T 0B , propeller torque Q 0B , hull trim value, hull sinking amount; according to formula (2), determine the force balance relationship of the oar; ΔZ=T 0B -R′ 0B (2) When ΔZ = 0, the propeller speed n0 is the ship's self-propulsion speed n B , and the corresponding R′ 0B 、T 0B , Q 0B are respectively the hull resistance R at the self-propulsion point B , propeller thrust T B , propeller torque T B Calculate the result data; when ΔZ≠0, reselect the propeller speed and return to step 2.2.6 to calculate until ΔZ=0; Step 2.2.8: Ship self-propulsion performance prediction method: Calculate the actual ship propeller received power P D ; P D =2*π*n B *Q B (3) The ship's self-propelled speed n B , propeller torque Q B .

6. A method for evaluating and optimizing the propulsion performance of a medium- and high-speed ship according to claim 5, characterized in that: The convergence judgment method is: S1: Based on formulas (4) to (7), the amplitude, amplitude mean and overall mean of the monitored values ​​of the ship's resistance, propeller thrust, propeller torque, ship's trim value and ship's sinking time history curve within the set oscillation period are calculated respectively; A i =R Pi -R Ti (4) Among them, A i , R Pi , R Ti They represent the amplitude, peak and trough of the i-th oscillation cycle of the curve respectively. It represents the mean amplitude of the 10 selected oscillation cycles; The mean is calculated using formula (6) and formula (7); Among them, R 0i , R0 represent the mean value of the i-th oscillation period of the curve and the overall mean value of the monitoring quantity in all 10 oscillation periods respectively; S2: Based on formulas (8) to (9), the convergence judgment conditions of the time history curves of hull resistance, propeller thrust, propeller torque, hull trim value and hull sinking value are calculated. Formula (8) is the ratio of the amplitude mean of the latest 10 change cycles of the time history curve to the overall mean of the monitored quantity is less than ε1, and ε1 is 5%; Formula (9) is that the percentage of the difference between the maximum value of the mean of the monitored quantity in each period of the time history curve and the overall mean is less than ε2, and ε2 is 1% to 2%; When all the time history curves obtained in this stage meet the convergence judgment conditions at the same time, the calculation is judged to have reached convergence, and the overall mean values ​​of the monitored values ​​calculated after the time history curves of hull resistance, propeller thrust, propeller torque, hull trim value, and hull sinking meet the convergence judgment conditions are respectively used as the hull resistance R′ corresponding to the initial speed n0 condition. 0B , propeller thrust T 0B and propeller torque Q 0B , hull trim value, hull sinking amount; the calculation process enters the next step.

7. A method for evaluating and optimizing propulsion performance of medium- and high-speed ships according to claim 5, characterized in that: The method for calculating the time step based on the minimum grid size is: Among them, Δt is the time step; is the reference velocity, which is taken as the incoming flow velocity in the computational domain; Δx is the minimum grid size in the flow direction, i.e., the x direction; C MAX is the Courant number, which is set to 10.

8. A method for evaluating and optimizing propulsion performance of medium- and high-speed ships according to claim 5, characterized in that: The initial speed n described in A1 o The calculation method is: A11: Estimate the initial thrust T0 of the ship according to formula (11); Where R0 is the overall mean value of the monitored quantity calculated based on the time history curve of the hull resistance, that is, the mean value of the ship resistance; t is the thrust reduction fraction, which ranges from 0.15 to 0.25 depending on the ship type; A12: Obtaining corresponding propeller open water characteristic data based on the ship type: the propeller open water characteristic data includes: the thrust coefficient K corresponding to the series advance coefficient J T , Torque coefficient K Q and open water efficiency η0 data; A121: Get thrust coefficient K T0 : Based on 75% of the maximum open water efficiency as input, interpolation is performed on the propeller open water characteristic data curve to obtain the thrust coefficient K T0 ; A13: Estimate the initial propeller speed n according to formula (12) o : Where ρ is the density of seawater and D is the propeller diameter.

9. A method for evaluating and optimizing the propulsion performance of a medium- and high-speed ship according to claim 8, characterized in that: In step 2.2.7, when ΔZ≠0, the processing method is: 1) If ΔZ < 0, it means that the thrust from the propeller cannot overcome the resistance of the hull, and the propeller speed needs to be increased. The new speeds n1, n2, and n3 are calculated using formulas (13) to (16), where K T0B The propeller thrust coefficient corresponding to the speed n0, ρ is the density of seawater, and D is the propeller diameter; n2=n1+(n1-n0) (15) n3=n2+(n1-n0) (16) Return to step 2.2.6, adjust the propeller speed to n1, n2, and n3 respectively, perform convergence judgment, and obtain the corresponding hull resistance R′ when the propeller speed is n1, n2, and n3 respectively. 1B , R′ 1B , R′ 1B Propeller thrust T 2B , T 2B , T 2B and propeller torque Q 3B , Q 3B , Q 3B At the same time, based on formula (2), the corresponding ΔZ1, ΔZ2, and ΔZ3 at three speeds are calculated; the hull resistance, propeller thrust, and propeller torque data at four speeds n0, n1, n2, and n3 are used, and ΔZ=0 is used as the input condition to perform cubic spline interpolation to obtain the propeller speed n that satisfies the condition of ΔZ=0. B 、Hull resistance R B , propeller thrust T B , propeller torque Q B ; 2) If ΔZ>0, it means that the thrust of the propeller is too large and the propeller speed needs to be reduced. The new speeds n1, n2, and n3 are calculated using formulas (13) to (16), where K T0B The propeller thrust coefficient corresponding to the speed n0, ρ is the density of fresh water, and D is the propeller diameter; n2=n1-(n0-n1) (15) n3=n2-(n0-n1) (16) The propeller speeds are adjusted to n1, n2, and n3 respectively, and the refined numerical simulation of ship self-propulsion is carried out using step 2.2.6, and the convergence conditions are reached, and the corresponding hull resistance R′ is obtained under the propeller speeds n1, n2, and n3 respectively. 1B , R′ 1B , R′ 1B Propeller thrust T 2B , T 2B , T 2B and torque Q 3B , Q 3B , Q 3B , and based on formula (12), the corresponding ΔZ1, ΔZ2, and ΔZ3 at three speeds are calculated; with the series data corresponding to the four speeds n0, n1, n2, and n3, cubic spline interpolation is performed with ΔZ=0 as the input condition to obtain the propeller speed n that satisfies the condition ΔZ=0 B 、Hull resistance R B , propeller thrust T B , propeller torque Q B .

10. A method for evaluating and optimizing propulsion performance of medium- and high-speed ships according to claim 1, characterized in that: Step 3.1 is a method for obtaining a three-dimensional geometric model file after the ship is deformed: using parametric modeling software, establishing a parametric deformation model of the ship's stern, changing the deformation parameters of the hull stern based on the hull deformation constraint conditions, realizing the transformation of the stern's three-dimensional geometric model, and obtaining a three-dimensional geometric model file after the ship is deformed.

11. A system for evaluating and optimizing propulsion performance of medium- and high-speed ships based on any one of claims 1 to 10, characterized in that: Ship type transformation subsystem: including: a ship tail deformation unit for establishing a ship tail parametric deformation model based on parametric modeling software; a ship type deformation parameter acquisition unit for changing the deformation parameters of the hull tail to achieve the transformation of the stern three-dimensional geometric model, and obtaining the three-dimensional geometric model file after the ship type deformation as the sample ship type three-dimensional geometric model file; The self-propulsion performance evaluation subsystem includes: a calculation domain unit for establishing a numerical calculation domain for the self-propulsion performance of a medium-high-speed ship; a medium-high-speed ship self-propulsion performance CFD numerical calculation model unit for conditionally configuring the medium-high-speed ship self-propulsion performance numerical calculation domain and establishing a medium-high-speed ship self-propulsion performance CFD numerical calculation model; a model control unit for establishing an automatic control method for the medium-high-speed ship self-propulsion performance CFD numerical calculation model; a ship self-propulsion performance numerical calculation model unit for establishing a medium-high-speed ship self-propulsion performance numerical calculation model in combination with the medium-high-speed ship self-propulsion performance CFD numerical calculation model and the automatic control method; a model calculation unit for inputting a sample ship three-dimensional geometric model file obtained by the ship transformation subsystem into the medium-high-speed ship self-propulsion performance numerical calculation model and calculating the power received by the ship propeller; Medium and high-speed ship self-propulsion performance optimization subsystem: including: a condition preset unit for setting the ship self-propulsion performance optimization target as the genetic algorithm termination condition, and a self-propulsion performance optimization unit based on the ship propeller received power obtained by optimizing the self-propulsion performance evaluation subsystem based on the genetic algorithm.

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